Methamphetamine use among gay and bisexually identified men (GBM) and other men who have sex with men (MSM) is strongly associated with HIV infection due to the concomitant high-risk sexual behaviors that often occur while using the drug. As a result, HIV prevalence is significantly higher among MSM that report frequent use of methamphetamine and highest among those meeting diagnostic criteria for methamphetamine dependence. Methamphetamine use among GBM and MSM is deeply integrated into socio-sexual networks including digital spaces such as cell phone applications, websites, and digital chat rooms used to hook up for sex. Given the available technology and advances in mobile health (mHealth) innovation, it is no longer necessary or reasonable to limit treatment options to physical brick-and-mortar sites. A computerized treatment intervention application (app) would provide a novel treatment opportunity that is easily accessible, private, and immediately available. Building upon the efficacy of the manualized, theory-driven methamphetamine- abuse treatment intervention, Getting Off: A Behavioral Treatment Intervention for Gay and Bisexual Male Methamphetamine Users, the proposed project seeks to establish the feasibility of translating this intervention into a computerized app. Like the evidence-based treatment intervention upon which it is based, the app will be designed to reduce methamphetamine use and HIV sexual risk behaviors and, among those who are HIV infected, increase antiretroviral therapy (ART) medication adherence. This application is in response to PA-12- 089, to stimulate a partnership of ideas and technologies between innovative small business concerns and non-profit research institutions. Consistent with the PA, the proposed project will conduct Phase 1 formative research, design and develop a cross-platform treatment app, and conduct a feasibility pilot test of the app. A methamphetamine abuse treatment app would capitalize on the ease in which GBM integrate technology into their daily lives and provide members of this extremely high-risk population with a treatment opportunity that is easily accessible, culturally-competent, and private. During the Phase 1 study, eight sessions of the 24-session intervention will be translated into an app format with input from focus group participants (N=24). The app will then undergo user feasibility pilot testing with a small number of participants (N=15). Both focus group and pilot participants will be representative of a typical consumer of the app. The app will be compatible with most smartphone/tablet devices (iOS and Android platforms). The specific aims are: 1) To conduct formative work to assist in the development of a culturally competent and consumer responsive computerized app based on the Getting Off methamphetamine-abuse treatment intervention for GBM; 2) To design and develop eight sessions of the Getting Off methamphetamine-abuse treatment intervention into a cross-platform computerized mobile app targeted to reduce methamphetamine use and HIV sexual risk behaviors and increases in ART medication adherence; and, 3) To conduct feasibility pilot testing and refinement of the eight session app.